Peaches threw the fruit to the Maltese Terriers Boris and Cassidy and Shih Tzu x Pug Gus while the family was out for the afternoon.
Unfortunately grapes contain a substance which can cause acute renal failure in dogs and could kill them.
When owner Helen Finch arrived back at her Nutley home, she noticed the grapes were missing and realised what had happened.
She took all three pups to Portland Vets in East Grinstead to be seen by vet Dr Anna Garvey.
She treated each with activated charcoal which helps prevent the absorption of toxins from the stomach and intestine.
The dogs were given intravenous fluids over the weekend to help to clear their kidneys. Tests confirmed no long-term damage and they have returned home.
Mrs Finch said, “Peaches flies freely around the house but returns to her cage when I’m not home. She’s a fantastic mimic.
“She called each dog over by name to be fed and dropped the grapes in front of them from her cage. Boris, Cassidy and Gus then tucked in to their illicit meal.
“I was horrified when I realised what had happened as I know how dangerous grapes can be.”
The vet added, “In cases of poisoning, speed of response is important so Mrs Finch did the right thing coming to us quickly as it meant we could flush out most of the toxins before they had a chance to cause serious harm to the dogs.”
Mrs Finch has decided not to keep grapes in the house in future.